SAN FRANCISCO - The White House threw its weight Monday behind a petition to end a ban on unlocking cellphones, the process of making a phone compatible with any carrier, not just the one that provided the device.

The move comes after the Copyright Office of the Library of Congress removed exemption status for unlocked phones, which means they would violate terms of federal law protecting copyright holders. Without their wireless providers' permission, consumers are subject to lawsuits from carriers for unlocking devices. The decision, made in October, went into effect in January and caused outrage among many digital rights advocates.

The White House's action was prompted by a petition posted on its "We the People" petition page by San Francisco resident Sina Khanifar. After it had received significant public support, both the White House and the Federal Communications Commission issued statements Monday supporting an end to the ban on unlocking.

"The White House agrees with the 114,000& of you who believe that consumers should be able to unlock their cellphones without risking criminal or other penalties" provided the phone is not under contract, senior White House technology adviser R. David Edelman wrote. "In fact, we believe the same principle should also apply to tablets, which are increasingly similar to smartphones."

Echoing those sentiments, FCC Chairman Julius Genachowski added that the ban "raises serious competition and innovation concerns, and for wireless consumers, it doesn't pass the common sense test."

Online protection

Put into effect in 1998, the federal Digital Millennium Copyright Act attempts to control consumer access to copyrighted material. In many respects it has provided protection for many media and content companies creating businesses online. The law also covers "take-down notices," which content creators can use to have their content removed from infringing websites.

But critics have argued that the copyright law's reach goes too far. Khanifar says the real issue is Section 1201 of the law, its "anti-circumvention" provision, which was intended to ban "black box" devices used to remove rights from digitally copyrighted works. Unlocked cellphones were previously exempted from devices covered by that provision, but that changed in October.

The Library of Congress - which oversees copyright law - responded to Monday's White House statement, saying, "The rule-making is a technical, legal proceeding and involves a lengthy public process. As designed by Congress, the rule-making serves a very important function, but it was not intended to be a substitute for deliberations of broader public policy."

While support for digital copyright reform from the executive branch is significant, Congress must act to make any change in the procedure. But Genachowski told online news site TechCrunch that his office is investigating whether it has the power to make changes without new legislation.

Big cellphone companies like Verizon and AT&T subsidize the cost of a smartphone for customers in exchange for them signing longer-term contracts, typically two years. Consumers can buy unlocked smartphones, but they usually have to buy them at full price.

Ken Dulaney, a cellphone analyst at Gartner, sees the White House's support as helpful. But he questions how many people would actually take advantage of unlocking should the decision be reversed. A lot of software for smartphones is carrier-specific, and many consumers don't know it would not be compatible on other carriers.

"You'd be better off buying an unlocked device to begin with," Dulaney said.